Magnetic latching solenoid

Abstract

This invention discloses a D.C. magnetic latching solenoid that retains a moving armature in a first or second position by means of a pair of magnets, thereby having a zero-power requirement after actuation. The first or second position is selected by reversing the polarity of the D.C. voltage which is enough to overcome the holding power of either magnet and transfer the armature to an opposite position. The coil is then de-energized.

What is claimed is: 
     
       1. A D.C. magnetic latching solenoid comprising: a. an electric coil;   b. a movable iron armature within the coil, said armature having a longitudinal axis and first and second ends;   c. first and second non-magnetic actuator rods attached respectively to the first and second ends of the armature on said longitudinal axis thereof, said rods passing through an aperture in first and second fixed magnets located proximate to the first and second ends of the armature, said magnets each having a like polarity adjacent the armature; and   d. a coil polarity reversing means connecting to the electric coil, wherein applying a voltage of a first polarity moves the armature in linear motion along the longitudinal axis to a first position and applying a reverse polarity voltage moves the armature in linear motion along the longitudinal axis to a second opposite position, and the armature is then retained in either position by one or the other of said magnets after the voltage is removed.   
     
     
       2. The solenoid as recited in claim 1 wherein the actuator is slidably affixed to a valve orifice to open and close a valve. 
     
     
       3. The solenoid as recited in claim 2 wherein the switch means is a double-pole, double-throw switch having forward, off, and reverse positions. 
     
     
       4. The solenoid as recited in claim 2 wherein the switch means is a triple-pole, double-throw switch for activating the coil and energizing one of a pair of position-indicating lights. 
     
     
       5. A D.C. magentic latching solenoid comprising: a. an electric coil;   b. a movable iron armature longitudinally aligned within the coil, said armature having first and second ends and a pair of non-magnetic actuators longitudinally aligned with said armature and fixed thereto;   c. a pair of fixed magnets in linear proximity to the first and second ends of the armature located on a longitudinal axis of the armature, said magnets each having a like polarity adjacent the armature; and   d. a coil polarity reversing means connecting to the electric coil, wherein applying a voltage of a first polarity moves the armature in linear motion to a first position and applying a reverse polarity voltage moves the armature in linear motion to a second opposite position, and the armature is then retained in either position by one or the other of the said magnets after the voltage is removed.   
     
     
       6. The solenoid as recited in claim 5 wherein the actuator rod passes through an aperture in each magnet. 
     
     
       7. The solenoid as recited in claim 6 wherein the actuator is slidably affixed to a valve orifice to open and close a valve. 
     
     
       8. The solenoid as recited in claim 7 wherein the switch is a double-pole, double-throw switch having forward, off, and reverse positions. 
     
     
       9. The solenoid as recited in claim 7 wherein the switch means is a triple-pole, double-throw switch for activating the coil and energizing one of a pair position-indicating lights.